Water-softening system for well-drilling units

ABSTRACT

A system for supplying a continuous flow of calcium-free water especially for use in oil-well-drilling operations that is portable in nature and is self-contained for automatic regeneration and structurally includes a storage tank for calcium-free water, a water softener unit, a brine storage tank for regenerating the water-softening materials, a brine maker tank, a bulk salt hopper, a piping system, pumps and controls for rendering the operation of the water softener automatic and also the regeneration of the water softener automatic to provide a continuous flow of calcium-free water for whatever purposes desired.

United States Patent Dexter E. Bruton Oklahoma City, Okla. 795,433

Jan. 31, 1969 Nov. 2, 1971 Southwest Factories, Inc.

[72] Inventor [21] App]. No. [22] Filed [45] Patented [73] Assignee [54] WATER-SOFTENING SYSTEM FOR WELL- DRILLING UNITS 3 Claims, 3 Drawing Figs. [52] [1.8. CI 210/89, 210/126, 210/191, 210/104 [51] Int. Cl B0ld 29/38 [50] Field of Search 175/66,

23/312 [56] References Cited UNITED STATES PATENTS 2,051,155 8/1936 Staegemann 210/89 2,192,451 3/1940 Moore 210/241 190M WA 7:? sup ly 3 2,460,036 1/1949 Sebald 210/137 X 2,571,247 10/1951 Huebotter 175/66 X 2,674,440 4/1954 Donovan 175/66 2,681,147 6/1954 Braswell... 210/266 3,286,839 11/1966 Lyall 210/89 X 2,395,258 2/1946 Drake.... 23/312 Al-I 2,988,221 6/1961 Culp 210/104 Primary ExaminerSamih N. Zaharna Attorneys-Clarence A. O'Brien and Harvey B. Jacobson ABSTRACT: A system for supplying a continuous flow of calcium-free water especially for use in oil-well-drilling operations that is portable in nature and is sel1fcontained for automatic regeneration and structurally includes a storage tank for calcium-free water, a water softener unit, a brine storage tank for regenerating the water-softening materials, a brine maker tank, a bulk salt hopper, a piping system, pumps and controls for rendering the operation of the water softener automatic and also the regeneration of the water softener automatic to provide a continuous flow of calcium-free water for whatever purposes desired.

PATENTEDN 2 SHEET 2 [1F 3 Dexter E. Bra/on INVI'IN'I'OK. man.

WWW Z? WATER-SOFTENING SYSTEM FOR WELL-DRILLING UNITS It is well known in the art that surface water or well water may contain harmful salts or other chemicals that adversely affect the viscosity and other properties of drilling mud. Also, when such waters are used as makeup water in water-cooling systems associated with drilling rigs, harmful deposits occur on the cooled surfaces such as in the passages of the cooling system of an internal combustion engine, the braking system of a drilling rig or the like. It is also well known that water sofl0 tener units employing ion exchange resins will effectively remove the harmful salts in various industrial processes. However, such systems are not adapted for use in oil well drilling.

Accordingly, the present invention relates to a continuous flow calcium-free water system used primarily in the treatment of drilling mud in the rotary system of oil well drilling and has for its primary object, the provision of such a system which is automatic in operation, dependable when left unattended for long periods of time thereby rendering the device economically feasible.

Another object of the present invention is to provide a water system in accordance with the preceding object which is self-contained and portable in nature and includes all of the components necessary for automatic regeneration and automatic operation and control so that a continuous flow of calcium-free water is supplied with a storage tank for such water being provided for providing a supply of calcium-free water during regeneration cycles or during emergency periods when water in excess of capacity of the water softener component is required.

By providing a calcium-free water system, the viscosity of the drilling mud may be more closely controlled thus improving the efficiency of the rotary method of oil well drilling. Further, calcium-free water when properly employed in a drilling mud will increase the yield of Bentonite or gel and also increase the effectiveness of all thinners and water-loss control agents. Also, the present system may be employed even with variations in the water pressure provided by the drilling contractors equipment and may be employed to utilize either AC or DC power from the drilling contractor's equipment thus rendering the device adaptable for installation under substantially any circumstances encountered in each individual installation with the installation being relatively simple and once made requiring very little attendance by personnel.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIG. 1 is a perspective schematic view of the water-softening system of the present invention;

FIG. 2 is a schematic sectional view illustrating the structure of the brine storage tank, brine maker tank and bulk salt hopper associated therewith; and

FIG. 3 is a schematic view illustrating the control circuits for the invention.

Referring now more specificallyto the drawings, the watersoftening system is constructed within a housing including walls 12, a floor l4 and, if desired, a roof or the like which may be in the form of a trailer or small house or enclosure capable of being placed on the bed of a truck or the like for transport to a desired location such as the site of an oil-welldrilling operation. Disposed within the enclosure is an automatic water softener 16, a brine storage tank 18, a brine maker tank 20, a storage hopper 22 for salt 23 used in regenerating the ion exchange resins (zeolite) in the automatic water softener 16. At one end of the enclosure, there is provided a storage tank 24 for soft water which is employed to supply soft water during the regeneration cycle of the water softener 16 and is also employed for an additional supply of soft water during emergency situations when the water demand is greater than the capacity of the water softener such as during periods of well drilling which require a large quantity of water for the drilling mud.

A water supply line 26 extends into the enclosure from any source available. For example, the raw, fresh water is pumped either from a surface source or well to the drilling-water-conditioning system by the drilling contractor's equipment. When entering the enclosure or equipment room, the raw water flows through a strainer 28 for heavy turbidity removal and this water then flows through a pressure reducing valve 30 which controls the water pressure throughout the system thus enabling the system to be employed with any type of supply equipment provided by the drilling contractor inasmuch as the pressure reducing valve 30 will supply raw, fresh water to the system at a predetermined pressure. The water under controlled pressure then will flow through a normally open solenoid valve 32 and this valve remains open during operation of the water softener 16. However, the valve 32 will be energized and closed throughout the water conditioning or water-softening regeneration cycle thus preventing raw water from being used for regeneration.

The raw water which has been strained and is under controlled pressure then enters the water-conditioning system or water softener and flows through the ion exchange bed contained therein for calcium and magnesium removal in a manner well known to those in this art.

The conditioned water then flows through discharge line 34 from the water conditioner or softener 16 to a normally open solenoid valve 36 which is normally open but which is energized and closed throughout the water conditioner regeneration cycle thus preventing bypassed water from entering the conditioned water storage tank 24 with which the discharge line 34 communicates. The solenoid. valve 36 will also be closed by liquid sensor probe 38 which will be actuated when the water level in the conditioned water storage tank 24 reaches a predetermined height to prevent tank overflow. After the water passes the solenoid valve 36, it passes through an automatic reset meter 40 which, after counting a predetermined amount of conditioned water passing into the storage tank 24, energizes and starts the automatic water-conditioning regeneration cycle. At the termination of the regeneration cycle, the meter 40 has reset itself and is again ready to count the quantity of water passing therethrough. The water then flows through a check valve 42 and into the storage tank 24 with the check valve serving to prevent a backflow of water from the conditioned water storage tank in the event any of the lines are disconnected for servicing.

With the conditioned water in the water storage tank, it is pumped out through a continuous action centrifugal pump 44 whichhas an inlet line 46 communicating with the bottom of the tank and a manual valve 48 provided in that line. The pump 44 has a discharge line 50 communicating with a line 52 which extends out through the wall of the equipment room to the drilling mud tank. A manual valve 54 is provided in the line 52 to close off the discharge to the mud tank with any suitable couplings being provided for the line 52 to the mud tank and also in the line 26 from the water supply.

When the system calls for a regeneration cycle, conditioned water will be pumped by the pump 44 to line 52 but a norm ally closed solenoid valve 56 will be opened and this valve is energized and opened throughout the automatic water conditioner regeneration cycle allowing conditioned water to be used for regeneration. Also, conditioned water as effluent of the water conditioner'l6 will flow through a nonnally open solenoid valve 58 which is energized and closed throughout the water conditioner regeneration cycle preventing brine system makeup and unstable brine draw. Conditioned water then flows to the brine maker tank 16 and when sufficient brine has been produced, liquid sensor probes 60 in the brine storage tank will deenergize and close solenoid valve 62 which prevents water flow to the brine maker tank 20.

The conditioned water flows upwardly through the brine maker tank 20 with the conditioned water being introduced 'through waterline 64 and entering the bottom of the brine maker tank as illustrated in FIG. 2. Upward flow of the conditioned water through the brine maker tank 20 will produce a concentrated brine. Flow control valve 66 in the waterline 64 for conditioned water regulates the water flow to the brine maker at a satisfactory rate to produce a saturated brine. The brine formed in the brine maker tank will overflow through overflow line 68 into the brine storage tank and brine 70 is withdrawn from the brine storage tank during the regeneration cycle. At the termination of each cycle, raw water is allowed to flow upward through brine draw valve 72, by position of special brine refill cam, to unseat the air eliminator balls in the brine draw valve located in the base of brine storage tank l8. When raw water flow rises in brine storage tank 18 to a height of approximately l inches, the float 74 being connected to the poppet in the brine draw valve closes, preventing further raw water flow and the brine storage tank 18 is then ready to receive brine from the brine maker tank 20.

The electric system is controlled by a control panel 76 mounted on the storage tank wall and will accept either AC or DC current and convert either current to supply both the AC and DC requirements of the system. The automatic reset meter 40 after metering a predetermined quantity of water from the water conditioner will energize a coil in the water conditioner control mechanism and place the water conditioner system in an automatic regeneration cycle. After performing this function, the meter 40 will reset itself to the original position to again meter water at the termination of the regeneration cycle. Throughout the regeneration cycle, the water conditioner control mechanism will close contacts that energize and reverse the position of the five solenoid valves. By utilizing a special brine refill cam to energize all five solenoids throughout the regeneration cycle, solenoid valve 36 can then be operated independently by the high water level controller 38 through an interlock relay in control panel 76.

Solenoid valve 36 performs two functions, namely, the valve will be energized and closed by the high water level control probe 38 when the water in the storage tank 24 reaches a predetermined high level to prevent tank overflow and the valve will be energized by the special brine refill cam throughout the regeneration cycle to prevent hard bypassed water from entering the storage tank 24.

Solenoid valve 32 will be energized and closed by the contacts on the brine refill cam throughout the regeneration cycle preventing raw water from being used to regenerate the water conditioner. Solenoid valve 56 will be energized and opened by the contacts on brine refill cam throughout the regeneration cycle allowing conditioned water from the centrifugal pump 44 to be used to regenerate the water conditioner. Solenoid valve 58 will be energized and closed by the contacts on brine refill cam throughout the regeneration cycle preventing water from entering the brine maker tank 20 throughout the period of time required for the water conditioners brine draw. A brine refill solenoid valve in commercially available control head 78 will be energized and opened by the special timer cam throughout the regeneration cycle plus minutes to allow the air eliminator balls in the brine tank valve 72 to be unseated at the termination of brine draw.

The high water level control 38 will energize and close solenoid valve 36 when the water level in the storage tank rises to a predetermined level to prevent tank overflow and this valve will be deenergized and opened when the water level falls to a predetermined height allowing conditioned water to again flow into the storage tank.

Lower sensors or probes 77 provide pump protection and will deenergize the pump starter coil when the water level in the storage tank falls to a predetermined low level to prevent the pump 44 from running in a dry condition. The holding coil in the pump motor will be reenergized when the water level rises to the uppermost of the two lower probes 77 to allow the pump to again deliver conditioned water to service.

The brine maker tank 20 is provided with a drain line 80 having a valve 82 therein and the brine storage tank 18 is pro vided with a drain line 84 having a valve 86 therein with both of the lines 80 and 84 being connected with a drainpipe 88 to enable these components to be drained when desired. Also, a drain line 90 is provided for the water-conditioning equipment and extends from the control head 78. Also, a manual valve 92 is provided in the conditioned water line 34 from the head 78 and a similar manual valve 94 is provided in the supply line extending into the control head 78 from the raw water supply or from the pump 44 during regeneration with all of these valves being standard commercially available valves installed in a conventional manner which is also true of the check valve 42 and various other manual and solenoid valves with the control head 78 being commercially available and the timer 79 for the water-softening device also being commercially available.

FIG. 3 illustrates schematically the control system which involves a power supply which may be either AC or DC which is fused at 102. From a panelboard 104, DC power may proceed directly to a DC pump motor 106 and also to a DC to AC converter 108 and provide an AC supply 110. If AC is provided, of course, from the panel 104, an AC supply 112 is directly provided and an AC to DC rectifier 114 is provided to provide DC power at 116.

From either AC source. power is supplied to a terminal board 118 through fuses 120 and the terminal board is electrically connected in a conventional manner to the brine level probe assembly 60 and the storage water level probes 38 and 77 and also connected to a relay 122 and various primary'and secondary coils 124 for the various motors and the like. The specific details of the electrical controls are not disclosed nor described herein inasmuch as such arrangement does not form any substantial part of this invention with it only being necessary to be able to be connected with either an AC supply or a DC supply depending upon what is available at the oil-welldrilling site and also to supply AC power as well as DC power for the various components of the system.

By employing the present system, a'continuous flow of calcium-free water for drilling mud used in the rotary method of oil well drilling may be provided which will operate with any available raw water pressure within the capabilities of the drilling contractors equipment and further it will operate on either AC or DC power whichever is available from the drilling contractor's equipment. Also, the salt hopper provides a continuous flow of salt to the brine maker tank and this system utilizes solenoid valves and liquid-sensing probes to activate the water-conditioning system through its regeneration cycle, brine producing cycle and conditioned water flow cycle. The timer and related equipment properly control the system with the control panel serving to convert the power for the system's needs and calcium-free water is used for system regeneration thus affording constant regeneration pressure in the system supplied by the system's own pump.

it has been found from actual experience that softening or removing calcium and magnesium from raw fresh water by the ion exchange method of the makeup water to the drilling mud in an oil-well-drilling operation will improve the quality and stability of the drilling mud. For example, Bentonite will yield better and lesser amounts of thinners and water loss control agents are required to produce a given quality of mud. By using this process, no soda ash is required in the system to treat out calcium. Thus, the total cost of the drilling mud in the process of drilling a gas or oil well can be substantially reduced. Also, by removing calcium and magnesium from the makeup water to the engine jackets of motors used in gas and oil-well-drilling operations, the amount of scale deposits in these water jackets can be substantially reduced. Further, removal of these materials from the makeup water to the drilling rig brake system, the amount of scale deposit can be substantially reduced therein thus providing a more efficient operation with less time required for cleaning water jackets and the like,

The entire system will preferably be housed within a metal structure or the like such as a dog house" that will be of adequate physical size to permit proper installation, servicing and operation with the overall system being of sufficient size to be loaded onto a trailer and moved from one location to another. The brine storage tank will be of sufficient size and capacity to hold an adequate amount of salt brine to regenerate the automatic water softener properly and efficiently and the brine maker tank will be of corresponding size and capacity to produce brine at the same rate it is used from the brine tank for the proper regeneration of the automatic water softener. The bulk salt storage container or hopper will automatically feed the bulk salt into the brine maker tank by gravity as the regeneration cycle frequencies demand brine from the brine tank. The bulk salt storage container will be of sufficient size and capacity to hold an amount of salt sufficient to meet the system regeneration demands for a predetermined time period.

The brine maker system includes a flow control valve to restrict the water flow rate to the extent that brine quality will be adequate at all times and there is a normally closed electric solenoid valve in the makeup water line to the brine maker tank and dual sensing liquid probes that at highest brine position will open an electric circuit and at any position below the high setting will close the circuit to the normally closed solenoid valve. Throughout the regeneration cycle of the automatic water softener a nonnally open electric solenoid in the makeup waterline will be closed by a special timer cam in the control head preventing water flow to brine maker during regeneration cycle. At the termination or regeneration cycle the special timer cam and sensing probe will have both sole noids in an open position. This will initiate a flow of water to the brine maker tank. when the predetermined high brine level in the brine tank has been satisfied, the probe mechanism will break the electric circuit thereby closing the normally closed solenoid and stopping the flow of water to the brine maker tank. The soft water storage tank will be of sufficient size and capacity to hold sufficient reserve water adequately to supply the demands of the operation to which the system is applied during the time that the automatic water softener is in a regeneration cycle and also serve as a standby water reserve for emergency demands.

in order for the invention to operate properly, a brine system is needed that will do the following:

I. Stop the flow of water to the brine system throughout the regeneration cycle of the automatic water softener. If water is allowed to enter the brine system during the regeneration cycle it would be making brine at the same time the water softener was withdrawing brine. This condition would make it impossible to regulate the exact amount of brine used by the water softener for regeneration.

2. The possibility of pulling air into the water softener head must be eliminated when the brine level of brine tank is down to the intake of the brine draw valve.

3. It is necessary to unseat the air eliminator balls contained within the brine draw valve at the termination of the water softener regeneration cycle. If valve balls are not unseated at this time it would be impossible to make another brine draw.

4. The flow of water to the brine system must be stopped when the brine tank is filled to prevent the brine tank overflow.

To accomplish the above requirements the following components ofthis invention are used:

1. Brine draw valve 72 and brine float 74. A commercially available brine draw valve and brine float perform two functions not only in this invention, but also in those applications of which they were originally designed. First, they provide a means of controlling the high level of liquid in the brine tank. In those applications for which the valve and float were originally designed, the liquid would be brine, and in this invention the liquid is water. Second, they prevent air from being drawn into the water softener head when the brine level is reduced to the intake opening ofthe brine valve.

The design of the brine draw valve is such, that in the lower section is a vertical spring-loaded check valve. This check valve has a spring on the underside and the seat on the top side. The flow of the brine is downward across the check valve then up to the water softener. The check valve moves downward and opens when brine is withdrawn. The brine float is connected to the top of the check valve poppet by a rod and a weight is attached to this rod. The upper section of the brine draw valve contains four vertical perforated tubes, one-half brine to flow downward into the brine draw valve and prevents the air eliminator balls from floating up into the brine tank. When brine is withdrawn it flows downward through the tubes around the air eliminator balls across the vertical check valve, then up to the water softener until the brine level drops to the level of the four air eliminator ball seats at the base of the tubes. The seating of these air eliminator balls, prevents air from entering the water softener head. i

2. Brine Refill Solenoid. This solenoid is an integral part of the water softener head 78, and no reference has been made to it heretofore. This normally closed solenoid is built into the water softener head 78, and does not have water available to' it when the water softener is in the regeneration cycle. As standard equipment from the manufacturer, this solenoid is ener gized and opened at the tennination of the water softener regeneration cycle by adjustable cams within the clock mechanism, for that amount of time required to fill a brine tank to the level desired for a specific application. These are cams that were modified in the invention. In the invention the brine refill solenoid is energized together with five other solenoids for the entire regeneration cycle, plus a 5-minute time period. The only requirement of the brine refill solenoid in the invention, is to institute an upward flow of water through the brine draw valve to unseat the air eliminator balls.

3. Brine tank float. With the air eliminator balls unseated by the upward flow of water into the brine tank it is necessary to raise and seat the check valve in the lower section of the brine draw valve to prevent filling the brine tank with water. The brine tank float being connected to the check valve with a rod, floats upward on the rising water and seats the check valve. The brine tank will now be filled with brine from the brine maker tank.

4. Brine tank probes 60, and normally closed solenoid 62. When brine is withdrawn for regeneration of the water softener the brine level within the brine tank falls away from the sensing probes, energizing and opening solenoid 62. This sole noid will remain open until the brine maker tank produces that amount of brine necessary to raise the brine level in the brine tank back to the level of the probe. Even though this solenoid is open, water will not be available to the brine maker until the termination of the regeneration cycle, when normally opened solenoid valve 58 is deenergized by action of the special timer cam. This will prevent brine making during the regeneration cycle, thereby, stabilizing the amount of brine that is withdrawn.

5. Normally open solenoid 58, This solenoid is energized by the contacts on the modified brine refill cam in the water softener for duration of the regeneration cycle, preventing brine tank makeupwhile the water softener is withdrawing brine.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

lclaim:

1. An apparatus for supplying a continuous flow of calciumfree water to a well-drilling operation for use as makeup water in drilling mud, said apparatus comprising a storage tank for conditioned water, a water conditioner discharging into said storage tank, means communicating a raw water supply with said water conditioner, pump means communicating with said storage tank for supplying conditioned water from said storage tank, control means operative in response to the quantity of water conditioned by said water conditioner, to terminate the water-conditioning cycle and start a regenerating cycle upon conditioning a predetermined quantity of raw water said control means including a meter between said water conditioner and said storage tank for measuring the quantity of conditioned water passing from said water conditioner to said storage tank, means for supplying a brine solution to said water conditioner during a regeneration cycle, said means supplying brine including a brine storage tank having means communicating with said water conditioner for delivery of brine thereto including air eliminator means for preventing the entrance of air into said water conditioner during the regeneration cycle, said control means including means for flowing raw water through said brine communication means and air eliminator means in response to completion of a regeneration cycle to condition said air eliminator means to prevent air from entering the conditioner on the subsequent regeneration cycle, a brine-making tank communicating with said brine storage tank for supplying brine thereto, said control means including means for supplying conditioned water through said pump means to said brine-making tank after completion of said flow of raw water through said air eliminator means after each regeneration cycle, brine level sensing means in said brine storage tank for disenabling said means supplying conditioned water to said brine making tank in response to a predetermined level of brine in said brine storage tank, said control means including means for prevent ing the flow of conditioned water to said brine-making tank during a regeneration cycle.

2. The apparatus set forth in claim 1 together with highlevel and low-level sensors in said storage tank operatively associated with said water conditioner and said pump means to stop the flow of water into said storage tank when the level of conditioned water therein reaches a predetermined high level and to disenable said pump means when the conditioned water reaches a predetermined low level to prevent operation of said pump means without conditioned water 3. The apparatus set forth in claim 1 together with a transportable enclosure surrounding said apparatus for transportation on a load-carrying vehicle to enable said apparatus to be conveyed to a site for use thereat. 

2. The apparatus set forth in claim 1 together with high-level and low-level sensors in said storage tank operatively associated with said water conditioner and said pump means to stop the flow of water into said storage tank when the level of conditioned water therein reaches a predetermined high level and to disenable said pump means when the conditioned water reaches a predetermined low level to prevent operation of said pump means without conditioned water.
 3. The apparatus set forth in claim 1 together with a transportable enclosure surrounding said apparatus for transportation on a load-carrying vehicle to enable said apparatus to be conveyed to a site for use thereat. 